The present invention relates to electrodeposition and, more particularly, to electrodeposition systems and methods that minimize anode and/or plating solution degradation during idle periods (i.e., non-plating periods).
Generally, electrodeposition (also referred to herein as electroplating) is a process in which plating material(s) such as one or more different metals are deposited onto a workpiece. Specifically, during electrodeposition, a first electrode with a workpiece to be plated and at least one second electrode are placed into a plating solution (i.e., a plating bath) within a plating container. Then, an electrical circuit is created by connecting a negative terminal of a power supply to the first electrode to form a cathode and further connecting a positive terminal of the power supply to the second electrode(s) so as to form anode(s). When the electric circuit is created, electric current flows from the anode(s) to the cathode by means of ion transport through the plating solution and electron transfer at the electrodes occurs such that each of the plating materials, which is/are dissolved in the plating solution as stabilized metal species (i.e., as metal ions), takes up electrons at the cathode, thereby causing a layer of metal or a layer of a metal alloy (e.g., depending upon whether a single or multiple metal species are used) to deposit on the cathode. The metal specie(s) in the plating solution can be replenished by the anode(s), if/when the anode(s) are soluble (i.e., if/when the anode(s) comprise soluble metal(s)) and the electric current causes the soluble metal(s) to dissolve in the plating solution). Additionally or alternatively, the metal specie(s) can be added directly to the plating solution.
Unfortunately, immediately following electrodeposition and, particularly, during an idle period after the first electrode has been disconnected from the power source and removed from the plating solution, any charged surface of the anode(s) can potentially cause unwanted reactions that result in anode degradation and/or plating solution degradation. Therefore, there is a need in the art for electrodeposition systems and methods that minimize anode and/or plating solution degradation during idle periods (i.e., non-plating periods).